Tasks in the form of promises and futures have in C++11 an ambivalent reputation. On the one hand, they are much easier to use than threads or condition variables; conversely, they have a significant deficiency. They can not be composed. C++20 will overcome this deficiency.
Mads Ravn, Antonis Polykratis, Martin Mancuska, David Farago, Edgar Rojas, and Adrian Javaloy.
C++20 will have atomic smart pointers. To be exact, we will get a std::atomic_shared_ptr and a std::atomic_weak_ptr. But why? std::shared_ptr and std::weak_ptr are already thread-safe. Sort of. Let me dive into the details.
The idea is quite simple. The Standard Template has more than 100 algorithms for searching, counting, and manipulating ranges and their elements. With C++17, 69 are overloaded, and a few new ones are added. The overloaded and new algorithms can be invoked with a so-called execution policy. Using the execution policy, you can specify whether […]
Forecasts about the future are difficult. In particular, when they are about C++20. Nevertheless, I will look into the crystal ball and write in the following posts about what we will get with C++17 and what we can hope for with C++20.
Expression templates are “structures representing a computation at compile-time, which are evaluated only as needed to produce efficient code for the entire computation” (https://en.wikipedia.org/wiki/Expression_templates). As needed, now we are at the center of lazy evaluation and the center of this post.
In my previous post, Recursion, List Manipulation, and Lazy Evaluation, I wrote about the characteristics of functional programming: The story about lazy evaluation in C++ is short. Sorry to say, but I have forgotten templates. The two advanced techniques, CRTP and expression templates, are based on lazy evaluation.
Ivan Cukic is currently writing a book on “Functional Programming in C++” for Manning Publication. Currently, 4 out of 14 chapters are published under the Manning Early Access Program. A new chapter is planned to appear each month. Here are the details of his book.
Monads in C++? What a strange name for a post. But it’s not so strange. With std::optional, C++17 gets a monad. The ranges library from Eric Niebler and the extended futures are also monads. For both, we can hope for in C++20.
We stay in the year 2020. With high probability, we will get concepts. Of course, waterproof statements about the future are challenging, but the statement is from Bjarne Stroustrup (Meeting C++ 2016 at Berlin).